Envelope or container



NOV. 28, 1944. Q 2,363,957

ENVELOPE OR CONTAINER Filed Dec. 2, 1942 INVENTOR: CE 50511: GOFF;

Patented Nov. 28, 1944 ENVELOPE OR CONTAINER George H. Goff. Fltchbllrg,Mesa, asslgnor to The Brown'Bag Filling Machine C R poration ofMassachusetts Application December 2, 1942, Serial No. 467,636

2 Claims.

The invention relates to envelope or bags suitable for use in automaticmeasure and filling machines for the packaging of pulverulent andsimilar materials.

Containers of this type have become of considerable importance withinrecent years, because of the greatly increased use of packages of goodsof various kinds put up in small quantities, and especially thoseadapted to be packaged by automatic packaging machinery. The generaltrend has been toward the development of fiat bags or envelopes, andnotwithstanding that numerous improvements have been made in suchcontainers there is still not complete satisfaction withthose'heretofore available, either because of excessive costs, orexcessive bulkiness of the container, faultiness of functioning of thepackage for the size of the contents, or otherwise, sanitaryconsiderations, and esthetic considerations, with possibly other effectsnot at this time enumerated.

It is therefore an aim of the present invention to effect a further stepof improvement toward meeting the objections noted as well as attainingadvantages in other respects. On account of the fact that gums used insecuring the closures of such packets being either capable of affordinga media for bacterial development or/and fungus propagation such asmold, as well as the antipathy of the public to having food come incontact with such adhesives, whether this antipathy is justified or not,it is an important aim of the present invention to embody a quickopening envelope suitable for use as a food container, and especially ofpulverulent foods such as flour samples, individual cocoa servings,andother materials, in which the contents will be protected from contactwith adhesive materials, not only whilethe package is sealed, but as itis opened and as the contents are discharged therefrom.

In prior envelopes it has been a serious objection that where theopening means consists of a bottom flap including both walls of a fiatenvelope folded on a crease entirely across the envelope and the flapthus formed detachably secured to the back of the envelope, when suchenvelope is opened by the pulling loose of the flap the creases in thepaper and the inherent tendency of the paper to retain its creased orfolded form cause the two walls of the envelope to tend to remainpressed together, interfering with the proper discharge of the contentsand requiring the user to insert the fingers into the end of theenvelope to press the walls apart, or to otherwise expend time andeffort in attaining this end, with poor success in many instances. It istherefore an aim of the present invention to overcome this objection,while retaining the advantages of the bottom flap of the general kind indicated. One of the principal reasons for the tendency of such pull-downbottom flaps to remain closed is the attachment or continuity of bothwalls of the envelope in the flap portions at the side fold of theenvelope, and it is an aim of the present invention toenable thecomplete disconnection of the extension of the front wall of theenvelope from the extension of the back wall in the bottom flap of theenvelope in an opening means of this general character. In detachablebottom flaps of this general type last mentioned. where the flap issecured to the back wall of the envelope by a weak adhesive, in suchmanner that the upturned flap may be pulled away from the back wall ofthe envelope and so detached therefrom, the attachment of the bottomflap to the back wall of the envelope has been lacking in security, andhas involved the liability of accidental opening of the passage, and itis an aim of the present invention to increase the security of theclosure while retaining all the advantage of great ease of opening andpossibility of rapid manipulation for that purpose.

In such envelopes means has not heretofore been devised to enable theuse of weakened lines in the paper stock to enable ready severance ofthe paper of the envelope along such lines: as will result in asatisfactory opening of the envelope. Recent developments of methods offorming weakened lines in paper stock have made this a very certain andeffective means for effecting severance of paper along arbitrary lines,with possibility of great range of direction and form in the severedparts, and it is therefore an aim of the present invention to enable theutilization of such weakened lines, especially those known as"perforations while retaining all of the advantages of a safe sealingofthe package against escape of pulverulent materials through suchperforations, corresponding to the result of a glued seam across theenvelope.

It is also an aim of the invention to provide such an envelope which maybe opened by the simple expedient of pulling a simple tab toward the endof the envelope while the opposite end of the envelope is held, andresulting in the opening of the envelope with full clearance of the contents for discharge, without delay or further manipulation to induce theseparation of the wall portions of the envelope at its opened end.

In the production of packages embodying this general style of openingmeans and in which a tubular container on a transverse line so thatparts of both the front and back walls are included in the fiapoutwardly of the line of fold and then securing this flap to the back ofthe package, dii'ficulty has been experienced where thin paper isemployed in the container. Very fine pulverulent material so packaged isfound to sift out by escaping between the two walls at the transversecrease or fold in the central part. Where the double wall fold is notemployed and a bottom flap on one wall is turned in around the bottomedge of the other wall of a continuous gum seal used so as to preventescape of fins material at the central part of the bottom, it is foundthat the content still escapes at each side of the bottom of the packagein the crease of the bottom flap. It is therefore an object of thisinvention to enable the use of my improved opening means in the lastnamed type of fold as well as a simple fiat bag closure where a bottomtongue on one wall is folded at and around the bottom edge of the otherwall.

Additional objects, advantages and features of invention may beunderstood from the following detailed description thereof, and theaccompanying drawing presenting the invention in its best knownembodiment. In the drawing,

Figure l is a plan of the paper blank for forming a fiat bag or envelopeembodying my invention.

Figure 2 is a back view of the bag partly completed, showing it in itstubular form Figure 3 is a back view of the lower end of the bagcompleted, and initial manipulation for its opening being indicated indotted lines.

Figure 3-a is an edge view of the bag showing a further stage in onemethod of manipulation for opening.

Figure 4 is a back view of the container opened.

Figure 5 is a fragmentary end view of the bag opened.

Figure 6 is a longitudinal sectional view of the lower end of a packageembodying my invention, and showing the initial manipulation for openingthe same.

Figure 7 is a longitudinal sectional view of the bag showing one mannerof final manipulation in emptying the package.

There is illustrated an envelope formed from a blank as shown in Figurel, which includes a body portion or front wall portion 2|, on which sideflaps 22 and 23 are formed, adapted to be folded inward on the creaselines 24, so as to overlap and form a back wall 25 of the container, asin Figure 2. At this stage the article may be termed a flattened tube.The side fiap 22 in this form of the invention is narrower than theother and is provided with a gummed zone 23 parallel to the vertical orlongitudinal edge of the flap, so that when this flap is folded over theother on the line 24 the two are secured together, so that the lappedportions of the back wall are paced from the medial longitudinal line ofthe envelope. From the top edge of the front wall portion 2i there isprojected a longitudinal closure tongue 21, conforming to usualpractices in such envelopes, and in the manufacture of this envelopethis closure tongue is uncoated with gum, so as to facilitate the use ofthe envelope in thebag filling machine, wherein gum. is usually appliedto this tongue incident to the sealing of the envelope by the machine.The side crease lines of the flaps 22 and 23 indicated at 24 by dottedlines are parallel to each other, and

seal is attempted by folding the end of a flattened the upper and lowerboundaries or the finished face of the front wall 2i are indicated byadditional dotted lines 23 and 23, respectively, defining arectangularboundary for the front wall 2|. The side flaps, and inconsequence, the back wall '2', extend upwardly beyond the defined faceportion of the wall 2i, as indicated by the line 23, but in Figures 1 to7, stop at the level of the line 23 defining the lower ends of thewalls. From the lower edge of the blank there is extended a closuretongue or bottom fiap 33, coextensive with the full width of the faceportion 2i of the envelope. This flap encloses a substantiallytriangular opener tongue area 3i, and in addition, integral sideportions 32 shaped as lobes having arcuate bounding edges, which, asviewed in Figure 1, are inclined downwardly and curved inwardly fromnear the base of the flap toward the longitudinal medial line of thefront wall 2i 9, distance, and are then recurved inwardly and upwardlyas at 33, to points spaced apart transversely of the container andlocated at the sides of a wide tab element 34, usually formed with awidth at its base' of an inch or more, Figures 3 and 4 being full sizeof an article as produced and used. The tab has a length longitudinallyof the blank from the points 33 appropriate to the use: hereinafterdescribed, and ordinarily less than one-half inch, the example shownbeing about one-quarter inch in depth. The base of the tab 34 preferablyis inwardly of the curved boundaries of the lobes 32, and spaced fromthe bottom line 29 of the front wall a substantial distance, and whilethis is not arbitrary, it has been 35 found in practice satisfactory tospace the base of the tab about-an inch from the line 23 On a container3% inches wide. The curves defining the outer edges of the lobes are, inthe present instance, substantially parabolic, with the axis of 49 theparabola nearer the tab than to the side tion of the flap includesfillets 38, which are small triangular areas of the blank integral withthe base body of the flap and with the flaps 22 and 23 respectively, atand. outwardly of the line 23, and outwardly of the lines 24, so that inthe folding of the side flaps on the lines 24 each crease formed extendsacross the junction of the fillet and the flap 30 and the fillet isturned. inward over the adjacent .portion of the base of the flap 30, asseen in Figure 2. Then, when the flap 30 is .folded on the line 23upwardly and inwardly onto the back wall 25, as shown in Figures 3 and6, the fillet is included within and under the folded fiap at eachcorner of the container, forming a complete closure and seal of thecrease. at each end and for a distance inwardly, and in addition,providing a terminal dam between the back wall 25 and flap 30 at eachend of the zone or area of abutment of the flap 30 and back wall 25. Theintervening lower edge of the back wall 2! lies snugly in the crease at20.

The lobes 32 have adhesive 33 applied thereto in zones spaced close tothe opener tongue area 3| and extending from immediately adjacent orincluding the fillets to the sides of the tab 34, or close to thelatter. i

There is also applied to the container either on the external face ofthe back wall "or the inner tearing of either the flap '30: srws r l*-The stripof special adhesive material stops at the diagonal edges ofthe' fillets, when the bottom flap is folded upwardand secured, and lieswith its ends within the defined area of the opening tongue 3| in thepresent instance, and is of a thickness approximately that of the paperof which the container is formed. Although this thickness has certainnovel advantages, as will be explained, it is not essential. The gum 36and adhering material 31 are applied by the envelope-making machineincident to the formation of the container, and the bottom flapimmediately folded upward against the wall 25, by the machine, so thatthe flap is secured fiat against the back wall. The material 31, extendsbetween or on to the fillets 35 in the completed container, so that thepartial dam formed by the fillets is completed by the material 31. Inaddition, the thickness of the material 31 presses the lower edge of theback wall snugly against the front wall so that sifting of fine materialfrom within a package around the bottom edge of the back wall isprevented. In addition, the material 31 forms a continuous attachment ofthe back wall edge and bottom flap so that possibility of separation ofthe front and back wall parts on the crease of the latter due todistortion of the package form is opposed. Such separations mightotherwise occur without the closely located continuous rectilinearattachment at 31, when the lower edge of a package is bent out of goodrectilinear form, or under various strains to which a package of thinpaper is readily subject, including, for instance, relative longitudinalmovements of the front and back walls, unequal pressures in transverselyspaced areas of the package, and otherwise. In this way, also,

likelihood of contents coming in contact with the.

material 31 is minimized so ,that some suitable simple adhesive may beemployed in the entire body of material 31, without requiring it to beof special quality, as to sterility, odor, or flavor. The momentarycontact involved when the package is emptied, as will be described, willbe of no material efiect.

Within the flap 30, the opener tongue 3| is defined by two lines orseries 38 of slits 39 formed through the paper of the blank at each sideof the area 3|, the series of slits being substantially rectilinear ateach side, and the series extending from adjacent the respective points33 to points close to the intersection of the side boundaries 24 of thefront wall 2| and the bottom line 29 defining the lower edge of the wall2|. These slits 29 are each formed in such manner that thereof.

though the paper is severed at the slit, the mate-- of objects strikingthe paper becoming engaged in any of the slits so as to tend to tear thepaper The slits in the present instance are so arranged that but few arerequired and are approximately spaced apart from each other oneeighthinch in the package of Figures 3-4, although this may be varied, or theends stop short of lapping, in some instances.

The slits 39 are inclined generally in a direction from'the lower corneror base of the bottom flap inwardly and upwardly toward the central r0ri Qn',Q ;the. ab;3 In the $l in t they areall locatedon lines arrangedatan angle to the base line 29 closely approximating 30 degrees, althoughthis angle may be somewhat varied without materially changing thefunction of the article. The downward inclination has a material effectin improving the opening function to be described.

In the present instance, there are but three slits in each series 38,but if shorter slits are employed more will be required. The parallellines on which the slits are located in each series as shown are spacedapproximately one-sixteenth of an inch apart, which affords goodstrength in resisting accidental disruption of the connection betweenthe opening tongue 3| and the holding lobes, while disposing the shortconnecting ribbon 4| between the lapped ends of the slits39 at suchangle to the direction of shearing stress in the opening operation thata maximum of ease in opening and a maximum definiteness of directionofseverance and separation of the tongue 3| and attaching parts isassured.

It should be noted that the tab 34 is formed with rounded outer cornersat its ends, its transverse edge being rectilinear, and its sides beingslightly divergent at its terminations and extending below the junctionpoints 33 of the curved edges of the lobes therewith. Thus, the base ofthe tab is defined at each side by short slits 49 extending into thefabric sheet a distance. This, in addition to the angle formed by thejunction of the lobe edge and tab edge, has an important function indefinitely determining the point of beginning of tear and alsofacilitating the tear, when the package is to be opened, as will bedescribed. At the same time the tab is held close against the back wallby the secured lobes 32 until opening of the article is deliberatelyprac ticed.

In the operation of opening the package, the package is heldapproximately erect in one hand, and the first and second digits of theother hand are presented with the finger nails next to the back wall 25and longitudinally inward of the transverse end edges of the tab, andthe nails engaged against this edge so as to separate it from the backwall and the same fingers pressed against its under side. The raised tabis then grasped between the same two fingers and the thumb and pulledoutward from the medial plane of the container and also longitudinallyoutward and downward toward the bottom edge of the package where thecrease line 29 is located. This causes the fabric to be torn beginningat the bottoms of the slits 40, and continuing longitudinally of thecontainer, until the tear at each side reaches slit 39 nearest to thetab. A substantial body portion of the tongue 3| extending alon thesetwoslits, is thus freed, and lifts out of the fiap30 without resistance bycontinued pull as described, until uns evered material at the lower endof the same two or uppermost slits 39 opposes the further lifting of thetongue. Continued 1ongitudinal pulling of the tab then causes theshearing of the outer (lower) extremities of the short ribbon-likeportion 4| between the first and second slits. Before this shearingoccurs, however, the ribbon-like portions permit a separation movementof the tongue ll therebelow away from terial is repeated at the lower orouter ends of the successive slits until, at the one nearest the bottomof the package, the final longitudinal shear, indicated at 42 in Figure4, reaches the bottom crease at 2911. By reason of the slight separationmovement of the body of the tongue 3| from the back wall 25, the body ofthe tongue is bent less sharply than ribbon part 4|, and shearing of thelatter is consequently easier and more definite in direction. Thecontents of the package serve to separate the front and back walls 2|and 25 of the container, and, as will-be understood, due to the inherentresiliency of the materials from which such bags are customarily formed,there is a stress set up in the walls of the bag by which the lowerportions of the walls tend to separate from each other at the line 29.

As the final tearing occurs and the tongue 3| reaches the extendedposition shown in Figure 7, the stress in the material of the containeras mentioned will cause its sides at th opening to spring apart, leavingthe contents free to fall, substantially as indicated. opened in thismanner it will have the appearance and arrangement of parts shown inFigure 5.

In prior bags of this general kind, where the projection of the backwall downward beyond the line of crease remains attached at the sides tothe front side portions or tongues, it tends to be moved to an angle tothe ,mean plane of the package, thus acting as a stiffening flange whichprevents free bending of that side of the opening, and opposesseparation of the walls, and also after a certain amount of the contentshas fallen from the package, the inherent resiliency of the materialcauses it to tend to close upon the remainder of the contents, so thatthe latter is opposed in its movement from the package; this objectionbeing overcome by the construction and arrangement above last describedin my invention.

It will be seen that by the utilization of the line of perforations orslits 38 in the relation and arrangement shown, it is made possible .0use an opening tongue separable by this means without liability of thecontents of the package escaping through the perforations. It will alsobe noted that by the use of the slits arranged as described, theweakening of the tongues 30 for thepurpose of severance is ample, yetthe paper is not so weakened againstbending that it will be likely tocrease or to bulge at the line of slits, and the tongue will lie fiatagainst the back wall of the envelope and maintain a complete seal atthe crease 2!|a. In the manipulation of the ackage for opening afterstarting the tearing out of the tongue 3|, it maybe held in invertedposition, as in Figure 3a, with one hand grasped around the containerwhile the tongue 3| is pulled longitudinally upward, after which thecontents may be poured from the open end of the container as found mostconvenient.

When the bag is aseaecr ticed, but if they are inclined as indicated,and if the upper ones in each series stop at their lower ends on linesat right angles thereto and across the upper ends of the slits nextbelow, it will be apparent that there will be a greater amount ofmaterial in the tongue opposing the sharp bending of the sheet materialat the point of shearing on each side, and consequently the bending ofthe paper will not be as sharp as in the ribbon-like parts ll whenopening is effected as described. But'the shearing will still occureffectively ordinarily if the pull on the tab is applied longitudinallyof the package, the sheer then extending longitudinally, andintersecting the next slit below near the upper end of the latter.

But if the pull on the tab should be exerted in a direction at aconsiderable angle to the longitudinal axis of the package toward oneside edge or the other at the lines 24, there would be a tendency forthe tear to extend into the body of the tongue 3| at the side oppositethe lateral direction of pull on the tab, instead of leading into thenext lower slit 39. A considerable variation from an exactlylongitudinal pull on the tab will be accommodated by stopping theproximal ends of mutually adjacent slits on a line at right angles tothe slits, but by forming the ribbon-like parts 4|, all uncertainty iseliminated, and in ad- .dition, the more effective shearing is accomofseparation, extending in a direction or directions having a substantialcomponent of the direction in which shear is to occur (or, in otherwords, the direction of pull applied to the parts to be separated), is amaterial factor in preventing mis-directed shearing, and eliminates suchfailures. When coupled with the lapped arrangement of the mutuallyadjacent ends of the slits, there is still greater certainty of definiteremoval of the complete area defined by the series of slits. Thedirection and arrangement of the slits is also material in enabling theuse of an exceptionally small number of slits and the wide spacing toafford ribbon yarts 4| of such substantial dimensions that likelihood ofcasual breakage of the package at the perforations is greatly minimized.The small number of slits as used is also afactor in assuring a heatershape to the torn-out part, as well; as contributing to the rapidity andcertainty of the opening operation.

The bag as described is adapted to beused in the conventional way inbag-filling machines where a large quantity of the containers are set ina bag-feeding box, in close packed relation and erect position, with thetop tongues or flaps 21 extending upwardly without being creased orgummed. The machine introduces a charge into the open upper end of thecontainer, and

creases the bag at the proper line, as well as applying gum on theclosing flap 21, as indicated at 43,, after which the closing tongue orflap thus formed is folded and squeezed so as to effectively seal thepackage.

Should the lapping of the slits 39 not be prac- 7 I claim:

1. A container of the character described comprising a blank of sheetmaterial having a front wall and two side flaps lapped to form a backwall, their lower edges forming a line across the container. a bottomflap extended integrally from the lower edge of said front walllongitudinally beyond said back wall and folded upwardiy at the saidlower edges of the back wall, fillets integral with the side and bottomflaps formed at each side of the junction of said bottom flap and saidfront wall and extended laterally from the lines 01 fold of the sideflaps and longitudinally beyond the line 01 fold of the bottom flap,said bottom flap having respective series of perforations at each sidedefining a substantially triangular centrati tongue having a broad basecoincident with the base of the flap and a narrow portion at theextremity of the flap, said flap including integral lateral partsoutwardly of and adjacent the narrower part of said tongue, an adhesivein permanent securin engagement between said lateral parts and the sbeing of a material structurally weaker than the a sheet material ofsaid blank.

2. The structure of claim 1 in which said strip' of material between thefillets is of a thickness substantially the same as that of the fillets.

GEORGE E. GOFF.

